Recent commits

New changelog entries:
* Tell haveged to create the pid file we expect.
* Give up and use systemctl to start haveged if running under systemd;
this shouldn't be necessary, but I can't seem to get things working in
the Ubuntu autopkgtest environment otherwise.

New changelog entries:
* Drop openssh-client-ssh1, now built by a separate source package.
* Run haveged during autopkgtests to ensure that they have enough entropy
for key generation (LP: #1712921).
* Apply patches from https://bugzilla.mindrot.org/show_bug.cgi?id=2752 to
allow some extra syscalls for crypto cards on s390x (LP: #1686618).